The present invention relates to a method of monitoring the actuation of an adjustment member of a control of an internal combustion engine, as for a motor vehicle, wherein the adjustment member is moved against a restoring force, and to an adjustment arrangement for the actuation of an adjustment member of a control of an internal combustion engine having a manipulator, such as an accelerator pedal, and having a linkage forming a mechanical connection between manipulator and adjustment member, which together form a force-transmission path.
In automotive vehicles, the engine as a rule is not located in the direct vicinity of the driver. When the driver wishes to accelerate the vehicle, or brake the vehicle with the aid of the engine, he must change the output of the engine. This is done, for instance, via a throttle-valve adjustment. Since the driver cannot directly operate the throttle valve or other adjustment elements such as, for instance, an injection pump, the adjustment, as a rule, is effected via a system of rods or a Bowden cable, or a combination thereof. An adjustment member is arranged on one end thereof while a manipulator which can be actuated by the driver, generally an accelerative pedal or a gas lever, is arranged at the other end. The force exerted by the driver on the manipulator is then transmitted to the adjustment member by the mechanical connection formed by the system of rods and/or the Bowden cable, as a result of which the adjustment member is displaced. In modern automotive vehicles the adjustment member no longer acts on the internal combustion engine directly but rather via the interposition of electro-mechanical or pneumatic setting members.
With the introduction of these setting members, it became necessary to effect monitorings and plausibility verifications. For example, electric signals for the control of the setting member are monitored for plausibility. In one special example, a switch is arranged on the accelerator pedal, the switch being closed when the driver actuates the accelerator pedal. Furthermore, a switch which opens when the setting member is moved out of its position of rest is provided on the setting member. If the setting member is now moved into a higher position, i.e. the setting-member switch opens, without the switch on the accelerator pedal being closed, it is to be assumed that something is wrong. In this case, the control will carry out an emergency program. The error control is in this case limited to the position of rest of the accelerator pedal.